Secretin receptor is a G protein-coupled receptor which binds secretin and is the leading member (i.e., first cloned) of the class B GPCR subfamily. Secretin receptor has been shown to interact with Pituitary adenylate cyclase activating peptide.

Secretin (SCT) occupies a unique position in the history of gastrointestinal hormones because it was the first to be discovered, in duodenal mucosa by Bayliss and Starling (1902). This 27-amino acid peptide stimulates the secretion of bicarbonate, enzymes, and potassium ion by the pancreas. Ishihara et al. (1991) isolated a cDNA encoding the rat secretin receptor. The nucleotide sequence showed that the secretin receptor consists of 449 amino acids with a calculated molecular weight of 48,696.